# Lesson 10

Completemos ecuaciones

### Lesson Purpose

The purpose of this lesson is for students to represent numbers 11–19 with equations.

### Lesson Narrative

In previous lessons students composed and decomposed numbers 11–19 with 10 ones and some more ones. They saw numbers 11–19 represented with written numbers, phrases such as “10 y 2” // “10 and 2,” expressions, and equations. In this lesson, students interpret equations and fill in the missing numbers to complete equations for numbers 11–19 (MP2).

• Action and Expression
• MLR8

### Learning Goals

Teacher Facing

• Represent numbers 11–19 with equations.

### Student Facing

• Escribamos ecuaciones para mostrar números del 11 al 19.

### Required Materials

Materials to Gather

### Required Preparation

Activity 3:

• Gather materials from:
• Make or Break Apart Numbers, Stages 1 and 2
• Bingo, Stages 1-4
• Number Race, Stages 1 and 2
• Grab and Count, Stage 1
• Tower Build, Stages 1 and 2

### Lesson Timeline

 Warm-up 10 min Activity 1 10 min Activity 2 10 min Activity 3 20 min Lesson Synthesis 10 min Cool-down 0 min

### Teacher Reflection Questions

What opportunities are you giving students to reflect on their understanding of the mathematical content?